Shift to the smallest cog, move the link to the lower run and squeeze it with master link pliers. Then check our brand-by-brand chart: SRAM 12-speed PowerLocks and Shimano QUICK-LINKs are single use, KMC R links are reusable.
Push the top of the wrench toward the back of the bike to loosen either pedal. The left pedal is reverse-threaded. Includes a direction tool, a stuck-pedal flowchart and install torque specs by brand.
Gear ratio is chainring ÷ cog; gear inches add wheel size; speed = gear inches × rpm ÷ 336. Compare two gears, see road, gravel and MTB low gears side by side, and find the cog you need to climb at your target cadence.
Find your bike’s headset code: check EC, ZS or IS, measure the bore or bearing, add the fork size, and avoid the IS41 vs IS42 mix-up. Includes a SHIS chart and free finder.
A 12×142 hub can take five different SRAM axles. Match diameter, hub width, length, thread pitch and thread length, with a free spec finder and SRAM’s catalog data.
Handlebar clamp diameter chart (22.2 to 35 mm), steerer and quill stem sizes, how to measure with a caliper or paper strip, shim rules, and a free tool that checks whether a stem fits your bar and fork.
Where your chain falls off points to the cause: front limit screws, a bent hanger, rear limit screws, chain slap, a loose ring or single-speed slack. Match your symptom with the chain-drop finder and fix it with Park Tool’s numbers.
Your seatpost size is the post’s exact outside diameter to 0.1 mm. Here’s how to measure it, a size finder, and which dropper posts and shims exist for 27.2, 30.9, 31.6 and 34.9 mm.
Center Lock and 6-bolt rotors aren’t interchangeable. Here’s what fits your hub, when an adapter works, and the torque and tools Shimano, SRAM and Magura specify.
Identify your bottom bracket from three measurements: threads, shell bore and shell width. Includes a finder tool, a sourced size chart (BSA, Italian, T47, BB86/BB92, BB30, PF30, BB386EVO), spindle fit and the right removal tool.